Bed setting drive with low-pressure hydraulic system

ABSTRACT

E.G. DEVICE FOR HYDRAULICALLY SETTING THE POSITION OF A BED WHICH INCLUDES A LARGE DIAMETER INFLATABLE HOSE TO WHICH IS CONNECTED A SOURCE OF LOW-PRESSURE WATER, E.G., FROM THE MAIN WATER SUPPLY. Inflation of the hose serves to move an element in contact with the hose surface and this element controls the position of the bed.

United States Patent [191 11 3,750,20U Hirmann 1 1 Aug. '7, 1973 -1 BEDSETTING DRIVE WITH [56] Relerences Cited LOW-PRESSURE HYDRAULIC SYSTEMUNITED STATES PATENTS [75] Inventor: Georg Hirmann, Zurich, Switzerland2,769,182 11/1956 Nunlist 5/68 2,725,093 11/1955 Saelen 5/81 R [73]Asslgneez Veenendaal & Co lndustnestrasse, 1,374,295 4/1921 Fleur,254/93 p Affolten a.A., Switzerland 2,632,898 3 1953 Pardoe 5/66 x 22 'ld: A 18 1972 I 1 Fl e Primary Examiner--Casmir A. Nunberg [21] Appl.No.2 245,081 Attorney-Alvin Browdy et al.

[30] Foreign Application Priority Data [571d f h d I h f e.g. evlce or yraulca y settmgt e position 0 a Apr. 19, 1971 Switzerland 5415/71 bedwhich includes a large diameter inflatable hose to [52] Cl. 5168 whichis connected a source of low-pressure water, e.g., [51] v Int Cl A4 fromthe main water supply. inflation of the hose serves Field of Search 5/6264 66-69' to move an element in Contact with the hose surface and thiselement controls the position of the bed,

9 Claims, 5 Drawing Figures PATENTEU M18 3,750,200

sum 2 or 3 PATENIEDMIC H915 SHEEI 3 OF 3 FIG. 3

FIG. 4'

FIG. 5

BED SETTING DRIVE WITH LOW-PRESSURE HYDRAULIC SYSTEM The presentinvention concerns a hydraulic lowpressure setting drive, in particularfor the operation of adjustable beds.

The object of the present invention is to provide a setting drive whichoperates with very low hydraulic operating pressure and which cantherefore be operated by an electro-hydraulic low-pressure pump or bythe water supply system direct.

The main advantage of such a bed-setting drive operated by the watersupply system is the outright elimination of any risk of explosion orfire in hospitals, where the care of patients often involves usingether, gasoline, etc., at the bedside, sothat the sparking of a switchor a fault in electric leads may result in disaster. The purelyhydraulic operation also rules out the danger of electrocution.

A cost advantage common to both operational versions exemplified is theexceptionally low manufacturing cost.

The low level of the operating pressure is ensured hereunder by theformation of exceptionally large active surfaces on the force generatorof the setting position drive.

The present invention is now to be described by way of example withreference to the appended drawings, in which:

FIG. 1 shows an embodiment comprising a bed with two new-type positionsetting drives incorporated;

FIG. 2 shows a position setting drive in perspective;

FIG. 3 shows a force generator;

FIG. 4 shows an arrangement for operating the setting drive from thewater supply system;

FIG. 5 shows an electro-hydraulic operation system for the settingdrives. FIG. 1 Bed with two new-type position setting drivesincorporated A bedstead 1 is provided with two main pivot assemblies 2and 7. The main pivot assembly 2 supports a pivoting part 3 providedwith a U-shaped tube 4. This tube presses against a piece of hose 5which serves as the force generator, and which is provided with closingcovers and whose inside is filled with a pressure medium. The piece ofhose 5 is supported by a channel 6 fixed to the bedstead l. The othermain pivot assembly 7 supports a pivoting part 8, as used for restingthe feet in a raised position, for instance; and connected to the freeend of the pivoting part 8 by a joint 9 is another pivoting part 10which is guided parallel to the bedstead by a link 11 movably joined tothe pivots l2 and 13. The two pivoting parts 8 and 10 are operated by aU-shaped tube 14 connected to the pivoting part 8 and by a piece of hose15 serving as the force generator. The latter, filled with liquid, issupported by a channel 16 fixed to the bedstead. When the pressuremedium e.g. water, is pumped into the piece of hose 5, the pivoting part3 rises in the direction of the arrow 47. Similarly, when the pressuremedium is pumped into the piece of hose 15, the pivoting parts 8 and ismove in the direction of the arrow 18. FIG. 2 Position Setting DriveShown in Perspective This figure shows the essential functional parts,namely the hose supporting channel w, the inflatable through a line 23.The hose is cylindrical and has a large diameter when inflated. FIG.3Hose Element This figure shows a hose element comprising a hose 24, anoutlet closing end cap or cover 25, an inlet connection or endcap 26,clamps 27 and 28 to control inlet and outlet, and a supply line 29. FIG.4 Operation of Position Setting Drives from Water Supply This type ofoperation is extremely simple, costsaving and safe. The figure showscomponents of the hydraulic assembly of a dual setting drive. A firsthose element serving as a force generator is connected by a hydraulicline 31 to a valve group, which in this case consists of two manuallycontrolled non-return valves 32, 34; the valve 32 when open admits thewater flowing from a pressure line 33, while the valve 34 when openpermits the water from the hose element to flow into the outgoing line35. Control of the other position setting drive is effected analogously.FIG. 5 Electro-hydraulic Operation of Position Setting Drives This typeof operation again uses water, but the con- 'struction is such as toprevent any loss of water. To

achieve this, a closed bag which is vented after being filled with wateris used as a reservoir.

The components shown in FIG. 5 are a bag 36, a pump 37, a dynamicallycontrolled change-over valve 36, a manually operated differential valve39, the hose element 40 of the setting drive, a differential valve 41and a hose element 42.

Raising of the pivoting part is effected by starting the pump 37 and atthe same time actuating the valve 39, e.g. by pressing the differentialpiston 43 in the direction 44, so that the valve disk 45 clears theaccess to the hose element 40.

Lowering is effected by actuating the valve 39, e.g. by pressing thedifferential piston 43, but without starting the pump 37.

The dynamically controlled change-over valve 38 consists of a piston 46with a coaxial through-bore whose cross-section is reduced with respectto the line 47, and a compression spring 43.

When the pump 37 is started, the pressure of the liquid moves the pistonin the direction 49 against the action of the spring 43 and closes theport leading to the line 50.

When the valve 39 or 411 is operated with the pump 37 switched off, thepiston 46 clears the port leading to the line 50, and the liquid returnsthrough the latter into the reservoir 36.

hose element 20, the U-shaped tube 21 resting on the 6 hose element 20and connected to the pivoting part 22. The hose element is supplied withinflating fluid I claim:

B. A device for hydraulically setting the position of a bed using lowfluid pressure comprising at least one elongated, radially inflatablehose having a large hydraulically active surface,

pivot assembly means for positioning the bed in response to theinflation of said hose, said pivot assembly means including an elementforming a concave deformation in the surface of said hose, through whichmovement of the surface of said hose is transferred to the bed, and

means to inflate and deflate said inflatable hose.

2. Bed-setting drive according to claim i wherein said element of saidpivot assembly means comprises a U-shaped tube the top of which isconnected to a'pivoting part of said assembly means and the base ofwhich forms said concave deformation in the surface of said hose.

3. A device in accordance with claim 1 comprising two said inflatablehoses for controlling the positioning of two separate portions of thebed.

4. Bed-setting drive according to claim 3 wherein each said hose issupported by a channel-shaped comdifferential valve.

9. In a device for setting the position of a bed using a low pressuremedium wherein the bed includes a frame and pivotal portion, comprisingat least one elongated hose portion closed at both ends, an elongatedrigid concave support channel for said elongated hose, said supportchannel being rigidly affixed to the bed frame, a transmission member incontact with and forming a concave deformation in the surface of saidelongated hose and operatively connected to the pivotal portion of thebed, and means to inflate and deflate said hose portion including asource of pressure medium and shutoff means.

o v UNITED s'EATEs PATENT OFFICE CERTIFICATE OF CORRECTION Patent3.750.200 Dated August 7, 1973 In n fl Georg HIRMANN It is certifiedthat; error appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

In the ABSTRACT, 1st; line, delete "e.g." and insert --A-- Column 2,line 13, after "element" insert --30-- Column 3, line 9 (claim 5),delete "8" and insert --l--.

Signed and sealed this 20th day of November 1973.

(SEAL), Attest: v

EDWARD M.FLET0111ER,JR. RENE D, TEGTMEYER Attesting Officer ActingCommissioner of Patents FORM PO-1050 (10-G9)

1. A device for hydraulically setting the position of a bed using lowfluid pressure comprising at least one elongated, radially inflatablehose having a large hydraulically active surface, pivot assembly meansfor positioning the bed in response to the inflation of said hose, saidpivot assembly means including an element forming a concave deformationin the surface of said hose, through which movement of the surface ofsaid hose is transferred to the bed, and means to inflate and deflatesaid inflatable hose.
 2. Bed-setting drive according to claim 1 whereinsaid element of said pivot assembly means comprises a U-shaped tube thetop of which is connected to a pivoting part of said assembly means andthe base of which forms said concave deformation in the surface of saidhose.
 3. A device in accordance with claim 1 comprising two saidinflatable hoses for controlling the positioning of two separateportions of the bed.
 4. Bed-setting drive according to claim 3 whereineach said hose is supported by a channel-shaped component. 5.Bed-setting drive according to claim 8 wherein water is the fluidmedium.
 6. A device in accordance with claim 5 comprising means forconnecting said means to inflate to main water supply.
 7. Bed-settingdrive according to claim 1 wherein said means to inflate and deflatesaid hose includes a low-pressure pump and a bladder-type reservoir. 8.Bed-setting Drive according to claim 1 wherein said means to inflate anddeflate comprises at least one differential valve.
 9. In a device forsetting the position of a bed using a low pressure medium wherein thebed includes a frame and pivotal portion, comprising at least oneelongated hose portion closed at both ends, an elongated rigid concavesupport channel for said elongated hose, said support channel beingrigidly affixed to the bed frame, a transmission member in contact withand forming a concave deformation in the surface of said elongated hoseand operatively connected to the pivotal portion of the bed, and meansto inflate and deflate said hose portion including a source of pressuremedium and shutoff means.